Abstract: To measure the bidirectional reflectance distribution function(BRDF) of the sample, measuring device with less light obscuration, large gyration radius and high positioning accuracy was designed. According to the requirement of measurement space and angle, the azimuth circle rail(Radius 1.3 m) and the zenith arc rail were designed to provide rotary orbit. Synchronous toothed belt were attached to the rails. Servo motors were assembled to realize the motion in two directions. The detector was installed on the zenith arc rail to achieve the sample detection in the range of 180 azimuth angle and 75 zenith angle. To avoid motion lag in the large size structure, the anti-jamming mechanism based on preloaded springs were designed, and the error analysis of introduced pointing accuracy was carried out. Finally, the pointing accuracy of the measuring device was measured. The experimental results show that the azimuth and zenith pointing accuracy of the measuring device is better than 0.147 and 0.358 separately. The measurement results are in agreement with the analysis results, which verifies that the designed BRDF measuring device meets the requirements of the indicators.